Not applicable.
Not applicable.
1. Field of the Invention
The present invention relates to a device for inducing a cycling motion in patients who have little or no motor control of their legs, and in particular, to such a device wherein the device includes a console for receiving the legs of the patient, the console having medial and lateral supports so that the legs of the patient are maintained in alignment during the cycling motion.
2. Brief Description of the Related Art
Stationary exercise bicycles are known for exercising by users who have motor control of their legs, but stationary exercise bicycles usually must be pedaled by the user and most have a way to increase resistance of the cycling motion in order to build strength and endurance.
It is known to passively exercise a wheelchair-bound person through a bicycle pedal arrangement driven by a speed-controlled electric motor. See, e.g., U.S. Pat. No. 5,033,736.
Likewise, U.S. Pat. No. 6,142,914 discloses an exercise device for use by a person sitting in a wheelchair. The device has a base which mounts onto the footrests of the wheelchair. The exercising device is adjustable on the base to accommodate the physical stature of the person sitting in the wheelchair.
In patients who have no (para- or quadraplegic) or little (multiple sclerosis (MS), cerebral palsy (CP), stroke or other fatigue and weakness-inducing disease) strength and control, cycling must begin very slowly and speed up with increases in strength. U.S. Pat. No. 6,142,914 notes that the device disclosed therein is operated at a slow speed but does not specify a particular speed as desirable. U.S. Pat. No. 4,824,104 also mentions starting the device at a slow speed. U.S. Pat. No. 3,212,776 discusses a device in which the action of the patient in opposing or working with the action of the motor causes a change in the torque applied by the mechanism to act as a compensator to smoothly resist any changes from its desired operating speed. A xe2x80x9cmaximum slow speed equilibriumxe2x80x9d of about 8 r.p.m. is suggested.
U.S. Pat. No. 4,846,156 discloses an exercise machine for use by a person in a wheelchair. The device includes both hand cranks and foot cranks. It is suggested that the lengths of the cranks may be adjusted to aid in aerobic exercise.
In a passive exercise device, care must be taken to protect the paralyzed/weak legs from misalignment or excessive stretch, which would lead to xe2x80x9clockingxe2x80x9d of joints during the cycling, in order to prevent injury. A form of medial support that prevents the legs of the patient from falling inwardly is suggested by U.S. Pat. Nos. 4,402,502; 4,572,501; and 4,587,960. U.S. Pat. No. 2,663,376 discloses a training device for crippled children, comprising a series of supports for the child patient, including a medially disposed guiding member and side frames.
Some devices explicitly address the problem of the legs of the patient falling outwardly during the exercise session. For example, U.S. Pat. No. 4,478,213 discloses an exercise device in which knee straps support the legs of the patient. Another solution to this problem is to employ supports about an upper portion of the calf to prevent the leg from falling either inwardly or outwardly. Devices of this type are shown in U.S. Pat. Nos. 5,951,442; 4,402,502; and 6,036,623.
The limitations of the prior art are overcome by the present invention as described below.
The present invention is a device for inducing a cycling motion in patients who have little or no motor control of their legs, for example, paraplegics, quadraplegics or those with MS, CP, stroke and similar diseases. The device comprises bicycle-type pedals connected via a belt or chain drive to a motor with a speed control mechanism, such as a rheostat. It is important that the device have a very low rate of rotation from 0.1 cycles per second up to about 1.0 cycles per second.
The apparatus includes means, such as clamps or straps for the wheelchair wheels, for locking a wheelchair in position such that the patient""s feet may be strapped into the pedals. It is important that the legs not be fully extended at any time to avoid possible injury to the patient. The device may also include means to adjust the diameter of rotation of the pedals to accommodate individuals of different heights, including children and adults, and to allow cycling of varying diameter. The device may operate with each leg independently. The motor is housed within a center console with medial and lateral supports so that the legs of the patient are maintained in alignment.
It is therefore an object of the present invention to provide for a passive exercise device for inducing a cycling motion in patients who have little or no motor control of their legs.
It is a further object of the present invention to provide for such a device having a very low rate of rotation from 0.1 cycles per second up to about 1.0 cycles per second.
It is also an object of the present invention to provide for such a device having a console with medial and lateral supports so that the legs of the patient are maintained in alignment during the cycling motion.
These and other features, objects and advantages of the present invention will become better understood from a consideration of the following detailed description of the preferred embodiments and appended claims in conjunction with the drawings as described following: